Suction cleaner



April 1s, 1933.

D. G. SMELLIE sUoTIoN CLEANER FiledJune 29, 1951 2 Sheets-Sheet 1 April 18, 1933. D. G. sMELLlE 1,904,973

SUCTION CLEANER Filed June 29, 1931 2 Sheets-Sheet 2 Patented Apr. i8, 1933 UNITED STATES PATENT OFFICE DONALD G. SHELLIE, 01B' CANTON, OHIO, ASSIGNOB, '10 THE HOOVER COMPANY, 0I' NORTH CANTON, OHIO, A CORPORATION OF OHIO BUCTION CLEANER Application led June 29, 1931. Serial No. 547,563.

' The present invention relates to suction cleaners in general and more particularly to a new and improved suction cleaner in which means are rovided to control the suction. 5 More speci cally the present-l invention comprises a suction cleaner in which means, either manual or automatic, are provided to control the cleaner suction through varying the motor speed. In its preferred embodimentthe l motorl speed is controlled \b variationsm the strength of'the field of t e motor wh1ch is accomplished through cutting in or out part ofthe field winding to effect an increase or a decrease in the field ampere turns. In

one of the preferred embodiments means are provided which are automatically actuated by variations in the cleaner nozzle suction and which function to control the suction through increasing` or decreasing the motor speed 1n accordance with suction variations.

It is an object of the present invention to provide a suction cleaner embodying new and improved suction-controlling means. A further object is the provision of new and improved means to control the suction of a suction cleaner. Still another object is the provision, in a suction cleaner, of automatic means for controlling the nozzle suction. A. still further object is the provision of means to control the nozzle suction which is automatic, and which is itself actuated by suction-variations. These and other more specific objects will appear upon reading the following speciication and claims and upon consideringin connection therewith the attached drawings to which they relate.

In the drawings in which preferred embodiments of the present invention are disclosed:

Fig. l is a side view of a modern suction cleaner in which the present invention is embodied;

Fig. 2 is a diagrammatic view of one em-` bodiment of the present invention in which manual means are provided to control the nozzle suction;

Fig. 3 is a modification of the embodiment shown in Figure 2;

Fig. 4 is an enlarged side view of a modern suction cleaner with certain parts of the nozzle and main casing broken away disclosing a preferred embodiment of applicants automatic suction-controlling means;

Flg. 5 is a partial top view of the cleaner shown in Fig. 4;

Fig. 6 is a diagrammatic showin of a preferred electrical hookup and apphcation of the automatic suction-controlling means;

l Fig. 7 isa modification of the automatic suction-controlling hookup.

In the modern suction cleaner it has been found desirable, in the interest of maximum cleanlng eiliciency, to raise the suction within the suction nozzle to a relatively high point. Increased suction results in increased air flow and in a given nozzle an increase in air flow results in greater cleaning effectiveness. In the modern cleaner the suction nozzle is supported movably at a distance above the surace Vcovermg undergoing cleaning which is picked, .1n the sense of bemg lifted, from the supportlng surface and held suspended against the lips of the nozzle mouth by the nozzle suction. With some types of surface coverin it is possible to so increase the suction wit 'I5 1n the suction nozzle that the coverlng w1ll beheld so tightly against the nozzle lips, and d1splaced to such a degree within the nozzle, that it becomes diiiicult for the operator to manipulate the machine. It becomes apparent, therefore, that beyond a certain suction value greater cleaning effectiveness must be sacrificed in order to prevent the energy re uirement of the machine in operation from ecoming too high.

In a suction cleaner constructed in accordance with applicants invention means are provided by which the suction within the suction cleaner nozzle is controlled so that, in one embodiment, when the cleaner is being used with a relatively light covering the suc- .tion may be decreased to accommodate the characteristics of that covering and, when being used upon a heavy covering, the suction value may be increased. In one preferred `embodiment of applicants invention means are provided which automatically control the suction value and prevent its reaching an excessive point on any type of covering.

Referring again to the drawings, and Figures 1 and 4 in particular, a modern suction cleaner is disclosed which comprises a main casing 1, including a nozzle 2, fan chamber 3, air passageway 4 connecting the nozzle and the fan chamber, and an exhaust outlet 5. A motor casing 6 is positioned upon the main casing 1 and houses a driving motor 7, a fragmentary section of which may be seen in Figure 4. A suction-creating fan 8 is carried by the extended end of the motor shaft within the fan chamber 3 while in the air passageway 4 a pulley 9 is mounted thereon. Pulley 9 drives the rotary agitator 10, of a well known design which is positioned within the nozzle 2, by means of a power-transmitting belt 11. An actuating handle 12 is provided which is pivotally mounted upon the main casing 1 by means of a forked bail 13, the handle eing hollow and being provided at its upper end with a grip 14. A dust bag 15 is provided which is secured to the exhaust outlet 5 at its lower end and to the handle 12 at its upper end. The incoming power lead 17 is shown provided at its outer end with a plug 18 and secured to the handle 12 adjacent the switch 19. The cleaner` is movably supported by wheels indicated by the reference characters 16 1c. The cleaner motor is preferably of the umversal type having a series field and is shown dagrammatically in Figure 2. Upon reference to that figure the field is seen to be in Series with the armature and to comprise two main branches F, and Fb. These fields are connected by leads 2O and 21 respectively to the female section of the detachable plug 22 which is positioned, as is shown in dotted lines in Figure 1, at the intersection o'fthe handle 12 and the bail 13. Connected in series with Fb is a. section of field winding which is indicated by Fc. This branch of the field is connected through the lead 23 to the third contact of the plug 22. The incoming power lead 17 from the plug 18 comprises two wires 24 and 25, the lead 24 connecting directly to a prong of the upper half of plug 22 while lead 25 is connected to the switch 19. This switch is of the two-way type which may be constructed in many ways, as for example in the manner shown in the patent to Krantz, 1,539,851, and has a movable trigger 26 provided with a contact 27 at its upper end adapted to selectively seat in either (f two seats 28 or 29. The lead 25 from the plug 18 is common to each of the seats 28 and 29.

Seat 28 is connected, through the lead 30, to the central prong of plug 22 by means of` tamtam.

18 being connected to the source of electrical power. Electrical current is conveyed tothe switch .19 and to one side of the electrical motor. With the switch trigger 26 in the ofi position, as shown in Figure 2, no current passes through the motor. On the trigger being moved either to the right or to the left a complete circuit is made and current is caused to flow through either seat 28 or seat 29. In the event the switch is thrown to the right, and seat 28 is closed by contact 27, electrical current fiows through the lead 30, across plug 22 to lead 23, and into the motor, the field FC being included. With the field winding Fc in the circuit the field strength is relatively great and accordingly the motor speed low. Inasmuch as the suction cleaner fan is connected directly to the motor the fan speed is accordingly slow resulting in a relatively low suction. With the trigger 26 thrown to the left, however, and seat 29 closed, electrical current is caused to flow through lead 31, across plug 22, and thence into lead 21, effecting the cutting out of field winding Fc. The motor circuit then includes only the armature and two field windings F,L and Fb. The field strength is then relatively weak and the motor speed relatively high. This results in a high fan speed and accordingly a high suction.

Referring now to Figure 3, a modified embodiment ofthe present invention is disclosed in which the motor 7 with its main field windings Fa and Fb is provided with additional windings FC and Fd. While in this specification the windings Fc and Fd may be spoken of as additional windings it is to be understood that it is within the scope of the invention that they should be merely portions of the main motor field which can be selectively cut from or added to the electrical circuit. In the present embodiment the threeprong plug of Figure 2 has been replaced by a four-prong plug 32 and to the female seats of this plug the fields FIl and Fb are connected by means of leads 33 and 34. The outer ends ofthe field windings Fc and Fd are connected, through the leads 35 and 36 respectively, to the inner two seats of the plug. In the present embodiment the incoming leads 37 and 38, from the plug 18, are both connected to the switch 19, which is provided with four seats 39, 40, 41 and 42. The incoming lead 38 is common to seats 39 and 41 while the lead 37 is common to the seats 40 and 42. From the seat 39 lead 43 extends to a center prong ofthe male half of the detachable plug 32 and is adapted to be electrically connected therethrough to the lead 36 connected to the field Fd. Similarly a lead 44 extends from seat 40 and connects it with the remaining central terminal of plug 32, so that seat 40 is directly connected electrically to field winding Fc through the connecting lead 35. Seats 41 and 42 are connected, by means of les leads` and 46 respectively, to the outer two prongs of the plug 32 and are adapted to be electrically connected therethrough to the leads 33 and 34 respectively, and so to the windings Fa and Fb.

To effect the closing of the seats in pairs trigger 26 is provided with twocontacts 27, 27 instead of one as in the previous embodiment. The movement of trigger 26 to the right results in the moving of the contacts 27, 27 to the left and the closing of seats 39 and 40. With seats 39 and 40 closed electricity enters by means of the leads 37 and 38, passes through the seats 39 and 40 into the leads 43 and 44, whence it is conducted through the plug 32 into the field windings Fc and Fd by way of the leads 35 and 36. As the windings Fc and Fd are in series with the main windings and armature of the machine it is apparent in this electrical hooku that a relatively great field strength is o tained. As in the aforedescribed embodiment this relatively greatfield strength effects a slow motor speed and a consequent low suction in the suction cleaner nozzle. With the trigger 26 moved to the left the contacts 27, 27 close the seats 41 and 42 effecting the passage of electrical current through the leads 45 and 46, through the plug 32 and into the main field windings F,l and Fb by means of the leads 33 and 34, thereby effectively cutting out the field windings Fc and F d from the electrical circuit. This latter hookup results in relatively high motor speed and consequent high suction.

Referring now to Figures 4, 5 and 6 a still further modification of the present embodiment is disclosed in which automatic means are provided for shifting the motor from high to low speed, or vice versa. Referring to Figure 4 in particular, a valve is shown positioned in the upper part of the nozzle 2 and which comprises a transversely extending plate or valve member which extends entirely across the nozzle, being pivoted at its forward edge as indicated at 51. Seals 52 and 53 are provided along the front and rearward edges of plate 50 which cooperate with the plate to provide a sealed pocket along the top of the nozzle. A rigid arm 54 carried by the rear edge of plate 50, extends up through an opening in the nozzle and pivotally connected to a lever 55 carried by the contact, or switch box, 56 mounted on the motor casing 6. A protecting cover 57 is provided which encloses and protects the extending arm 54 and the contact box 56, as is clearly shown in Figure 5, though it does not seal the pocket formed by valve 50 from the exterior atmosphere.

In the interior of contact box 56 is provided a switch 58 of the snap type. Reference to Figure 6 discloses the electrical connection of switch 58 and its modus operandi. In that figure the motor 7 is shown provided with the main field windings Fl and Fb and the auxiliary winding Fc. A lead 59 connects the motor with the power cut-off switch 19 which is itself connected to an incoming power lead from the external plug 18. The opposite side of the motor is provided with two leads 60 and 61 which connect directly to the fields F b and Fc, respectively. At their opposite ends the leads 60 and 61 are connected to a side of the seats 62 and 63, respectively, of the switch 58. A lead 64 is connected to one side of the plu 18 and is common to each of the seats 62 an 63. The switch 58 comprises a snap-actuated contact 65 which is adapted to assume a seating position within either of the seats 62 or 63 depending upon the position of the lever arm 65 whose position is controlled by the valve 50 operating through the arm 54. A s ring 66 is provided which maintains the val)ve 50 and lever 55 in the upper position, in the inoperative relationship,

serving to close to the switch seat 62 and so form an electrical circuit through the lead 60 into the fieldFb, cutting out from the motor circuit the field winding Fc.

In the operation of this embodiment of the l invention, upon the closin of the switch 19 electrical current passes vt rough the motor circuit excludin the winding Fc. The motor is then in its hig speed relationship. As the suction within the nozzle 2 is increased thev surface covering is lifted and contacts the nozzle lips. With this contact the suction value increases and, if the type of covering be such that the suction value is increased to `an undesirable extent, the contact 65 is snapped from the seat 62 to the seat 63, resulting in the inclusion of the field winding Fc in the motor circuit. This change in the position of switch contact 65 was accomplished through the following operation: As the suction within the nozzle 2 increased, valve 56 was drawn downL into the nozzle against the tension of spring 66. lrihis functioning is obvious inasmuch as plate 50, with the seals 52 and 53, is exposed to atmospheric pressure on its upper surface and to the nozzle pressure on its underside. In the inoperative relationship the plate 50 is held in the dotted iine position shown in Figure 4, by

the tension of spring 66. Upon the decrease in the pressure in the nozzle 2, however, valve 50 is drawn downwardly into the nozzle, resulting in the downward movement of the arm 54 and the consequent pivoting of lever 55. The switch contact 65, however, moves with a snap action and, until the arm 54 has been lowered to a predetermined extent, no change in the switch position occurs. It is apparent that in the operation of this embodiment of the applicants invention vthat increase of the nozzle pressure beyond a predetermined extent is impossible.

In the embodiment of applicants invention, shown in Figure 7, the automatic actuating mechanism described in connection with the aforedescribed embodiment, is used. The two-way switch 58, however, has been eliminated and in its place has been rovided a series of contacts 67, 67 etc. w ich are adapted to be contacted by the movable contact 68 carried by the lever 55. These contacts. are connected to the auxiliary field winding Fc, which is tapped as indlcated. In the operation of this embodiment of the invention as the suction within the nozzle varies and the valve is ex anded or collapsed, field winding Fc willxbe added or removed by increments or decrements, depending upon the position of contact 68 relativeto the contacts 67, 67. As arm 54 is moved downwardly, indicating an increase in suction value, the arm 55 will be pivoted in a clockwise direction, resulting in the movement of contact 68 upwardly and resultin in the inclusion of a greater partof the field Fb in the motor circuit. This additional winding necessarily results in a greater lield flux and a reduced motor speed, thereby effecting a reduction in suction. The determination of certain constants and the rovision of adequate taps 67 67 on the auxihary winding Fc insures a predetermined suction in the cleaner at all times and under all operating conditions.

I claim:

l. In a suction cleaner, a casing including a suction nozzle having spaced surface-contacting lips, a fan open to said nozzle, an electric motor connected to said fan, and mea-ns to reduce the suction in said nozzle upon said suction passing a predetermined point in order to limit the covering displacement in said nozzle between said lips, said means comprising meansto control the speed of said motor, a pressure-responsive device in the nozzle exposed to the pressure therein, and means connecting said pressure-responsive device to said speed-controlling means.

2. In a suction cleaner, a casing including a suction nozzle having spaced surface-contacting lips, means supporting said casing with said lips spaced above the normal surface covering plane in the operation of the cleaner, an agitator in said nozzle adapted to contact the surface covering undergoing cleaning, suction-creating means including a motor and a anconnected to said nozzle and adapted to create a reduced prcure therein to lift the surface covering undergoing cleaning into contact with said lips and said agitator, and means to control the suction in said nozzle to prevent undue cover` ing displacement and resulting excessive friction in the movement of said agitator thereover, said means comprising motor-speedcontrolling means, and preure-responsive means in the nozzle exposed to nozzle pressure and connected to said speed-controlling means to actuate the latter to decrease the p iotor speed upon an increase in nozzle sucion.

3. In a suction cleaner, a casing including a suction nozzle having spaced surface-contacting lips, means su porting said casing with said lips s aced a ove the normal surface covering p ane in the operation of the cleaner, an agitator in said nozzle adapted to contact the surface covering under oing cleaning, suction-creating means inclu ing a motor and a fan connected to said nozzle and adapted to create a reduced pressure therein to lift the surface coverin undergoing cleaning into contact with sai lips and said agitator, said motor being provided with a tappked field winding, switch means connected to t e tapped winding, and pressure-responsive means in the nozzle exposed to the pressure therein and connected to said switch means to vary the field of said motor upon nozzle suction variations. Signed at North Canton, in the county of Stark and State of Ohio, this 18th day of June, A. D. 1931. DONALD G. SMELLIE.' 

